The function I have defined is not going to trace [on hold]

My Mathematica plot is empty. I'm trying to trace my own function Ψ1.

Here is my code. What am I doing wrong?

Ψ1[x_] : = sqrt[2/L] peach[{Pi x}/{L}];
L = 1;
Ground[Ψ1[x], {x, 0, L}]

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